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JW <none@dev.null>: Sep 15 09:21AM -0400 On Wed, 14 Sep 2016 07:11:26 -0400 JW <none@dev.null> wrote in Message id: >reputable source that would back that up.   >Can't find one, can you? Maybe jeanyves can?   >Bet not.   [crickets]

root <NoEMail@home.org>: Sep 15 04:03PM > [crickets]   Completely off Topic:   I laughed at your response, then I started to think about whether [crickets] means the same thing to you that it does to me.   I take it as a reference to a Bugs Bunny/Daffy Duck cartoon about a contest to see which was funnier. Is that your reference?

pedro <me@privacy.net>: Sep 11 02:14PM +0800 On Sat, 10 Sep 2016 23:16:55 +0800, "Mr. Man-wai Chang"   >I knew it's impossible to use a chip to prevent abuse.   then you're smarter - or dumber - than some.

Chris Jones <lugnut808@spam.yahoo.com>: Sep 09 12:48AM +1000 On 08/09/2016 19:17, pedro wrote:   > Well the winding wire will be heavier gauge at 24VAC. Whether that > will achieve a more reliable ROHS solder bond is unsure, but it > probably couldn't be any worse.   It is possible that the solder has dissolved too much of the fine wire, making it too thin. I have had a lot of trouble soldering very fine wire, especially with lead-free solder - the wire will get thinner as it dissolves in the molten solder, leaving it even less robust than its original fragile state. Leaded solder that was deliberately pre-saturated with copper ("Savbit") was supposed to be good for preventing that, but I found it generally unpleasant to use.   As your coils develop their faults over time, I also wonder if the manufaturer left some fairly active flux inside the encapsulation that might be slowly eating the wire near the solder joint when it is warm.   Perhaps you can tell whether the break is at the solder joint, by measuring the low-frequency capacitance of each terminal of the damaged coil with respect to everything else. I doubt that knowing where the break happens would be much use to you, but it is something the manufacturer should be looking into.

pedro <me@privacy.net>: Sep 09 03:54PM +0800 On Thu, 8 Sep 2016 18:36:23 +0100, Mike Tomlinson <mike@jasper.org.uk> wrote:   >coils, and you're /assuming/ RoHS lead-free soldering is to blame >without having (yet) found evidence, perhaps you could look at other >common factors.   Fair comment.   >Is the supply voltage to the coils stable, for instance? Voltage too high?   Without logging it (and I don't have access to a Dranetz any more) I would venture that it is. Reading taken at random times show good regulation, and nothing else in the place which is surge-prone (electronics and incandescents) is dying at all.   >Loose connection causing unstable voltage/surges/sags at the >coil?   Nope, snug as.

pedro <me@privacy.net>: Sep 09 04:09PM +0800 On Thu, 08 Sep 2016 08:17:12 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >What do you measure for coil DC resistance?   Missed that bit. Around 1600 ohms.

pedro <me@privacy.net>: Sep 09 03:50PM +0800 On Thu, 08 Sep 2016 08:17:12 -0700, Jeff Liebermann <jeffl@cruzio.com> wrote:   >would be interesting to know what temperature the solder joint is >experiencing. A thermistor or thermocouple glued to as close to the >solder connection as possible might provide some interesting numbers.   Indeed. It would be handy to have a thermoprobe with logging on it. Note to self: see where I can borrow one.   >If the position of the solenoid above the oven is the problem, that >will show it. Perhaps adding a metal heat shield between the coil and >oven?   The dual valve mechanism is bolted to the oven. The coils (see ebay item# 322017672259 for the ones we "consume" - but at a much better price than he's asking ...) sit over the metal housing which encloses the valve plunger (armature) and has a metal spacer each end for location and ?thermal separation?. So it would be necessary to elevate the entire incoming gas pipe/valve syhstem to relieve conducted heat to any significant degree. And if it IS the cycling - rather than the actual temperature reached - which causes the failures then reducing the latter may achieve nothing.   >wire survive. With an inductor, there should NOT be an inrush peak, >but I'm thinking some kind of glitch, spike, or peak might be arriving >via the 240VAC line.   Dunno. Could do (but it'd be 18 months before I'd know if it made a difference).

Ralph Mowery <rmowery28146@earthlink.net>: Sep 09 03:37PM -0400 In article <qfp5tbdui7tp06noacl0sjeotnm34182fu@4ax.com>, jeffl@cruzio.com says...   > Also, could you check the eBay listing number? I want to see the coil > specs. Nothing found: > <http://www.ebay.com/sch/i.html?_nkw=322017672259>   Jeff I think you are mixing up the AC and DC power formulas.   I am sure the impedance of the coil at 60 Hz is more than the DC resistance.   That would make the wattage less than what you have calculated using a DC equation.   A quick check of the Goyen catalog shows they draw about .05 to .07 Amps depending on the coil at 240 volts. That is around 10 to 16 watts. The DC resistance of the coils was not given. The coils on many of the valves can be changed to several voltages.

pedro <me@privacy.net>: Sep 10 12:02PM +0800 On Fri, 9 Sep 2016 15:37:02 -0400, Ralph Mowery   >Jeff I think you are mixing up the AC and DC power formulas.   >I am sure the impedance of the coil at 60 Hz is more than the DC >resistance.   The DC resistance averages around 1600 ohms. According to my calcs there are around 4700 turns in the coil, so at 50Hz the impedance incorporates a significant reactance. The coil (obviously) has a ferrous valve plunger in its core.   They are marked 240VAC 50Hz (= our supply here in Oz) and the one I attacked with the Dremel is marked 5W.

pedro <me@privacy.net>: Sep 10 12:02PM +0800 On Fri, 9 Sep 2016 10:03:15 -0400, Ralph Mowery   >Have you looked into another valve company ?   No   >I retired a few years ago from a large company and we had hundreds of >valves similar to that and very few of them failed, especially the >coils. Most did operate on 120 volts.   Of course at 120V the wire would be twice the diameter. If it is corrosive flux at work, it would take longer to eat it away. If it is failing Pbfree solder bonds, who knows.   >Not sure how the valves are in your oven, but maybe you could try 2 of >the 120 volt coils in series.   I am considering that. Meanwhile SWMBO is considering a replacement oven (which as you'd all know, means a complete new kitchen)

dplatt@coop.radagast.org (Dave Platt): Sep 09 05:46PM -0700 In article <fs26tb9arnl6jp2cam08qra6urtj1mjsoc@4ax.com>, >out of the music while the amp turns back on!   >Good grief, the idiot engineer who designed this! I hope he got his pink >slip.   I sorta expect that this isn't a problem for the product's intended demographic: the very large number of young folks who listen to modern pop music, which simply doesn't *have* any 10-second quiet periods in it. It's all been loudencompressified to death, has a total dynamic range of maybe 3 dB on a really good day, and is either THERE or ( )   Thanks for the warning, though - I won't buy such a monstrosity myself. I have this atavistic preference for dynamic contrasts and subtlety in the music I play...

bruce <bruce@invalid.dyndns.tv.invalid>: Sep 14 06:41PM -0400 > NOTE: The SSID has nothing to do with the question but people get all hung > up if I ask the question this way:   > Q: When does an Android cellphone broadcast a BSSID?   Oh, what the hell. I'll give it a try.   In the following I tend to intersperse WAN and LAN as well as BSSID and MAC. The basic underlying concepts work in both environments (with some fudging).   SSID has nothing to do with cellphones. It has to do with wifi only. The same is true for BSSID.   SSID is just a name. There could be thousands of wifi access points around the world with the same SSID.   A wifi access point consists of one or more radios to create a WAN. Each radio is a BSS with a BSSID, which is also known as a MAC. Each network device/radio has (by design, but not always in fact) a unique value for the MAC.   A device wishing to connect to a wifi access point looks for a broadcast wifi packet with a particular SSID in the data field of the packet. The header to the packet contains the BSSID/MAC of the access point in source field. To connect to the access point the device sends a packet back to the sender of the broadcast by putting the access point's BSSID in the destination field of the packet and its own MAC in the source field. The rest of the connection protocol is left as an exercise for the reader.   Until things get handed over to (presumably) DHCP there is no way to communicate other than the use of MAC addresses in the appropriate fields of the LAN packets. Strictly speaking, even after an IP address is assigned to the device, all communications on the LAN/WAN is still through the use of BSSID/MAC. It is only after a packet is recieved by the router that higher levels of network communications kick in and a packet will be repackaged with the necessary outer packet to make its way to the internet.   So, "Q: When does an Android cellphone broadcast an SSID?"   A: Keying on the use of the word "broadcast" and ignoring the use of the word "cellphone" because it doesn't apply, only when it is acting as its own access point/hot-spot for other devices. After all, an SSID is only a name.   And, "Q: When does an Android cellphone broadcast a BSSID?"   A: Again, keying on the use of the word "broadcast" and ignoring the word "cellphone" the answer is the same as for the previous question. However, as mentioned earlier, the MAC/BSSID is used in every packet that is sent back and forth with the access point, but is strictly usable only within the geographic area that the radio signals reach, which is pretty much limited to line of sight communications and for which walls are only semi-transparent at those frequencies.   Now, with all that said, there is in theory nothing to stop any program running as part of the wifi access point or within the connecting device to query its own networking internals to grab its own MAC address or the MAC address of devices it is communicating with and send that info out onto the internet to some recipient along with info from its own GPS, if available.   So, while it is not part of the normal protocols to reveal that information it is not inconceivable that some user level program could be doing the nasty deed.   Furthermore, all of this is at best fleeting information because a network device's MAC address is held in ROM on the device. The network software in a device reads the ROM to get the MAC, but is in no way required to use that address when constructing packets that will go out the device. The device itself *DOES NOT* insert the address into the outgoing packets. That is all handled by software. Therefore it is trivial for the software to use whatever MAC address it wants for its outgoing packets. This is in fact how DECnet used to work, the two high order bytes of the MAC were changed to reflect the fact that a packet was a DECnet packet.   As was said before, just flip a few bits and you could suddenly appear to be on the other side of the planet.   Whew!   Now, what has been left out? Oh yes, the cellphone network. How data is sent over the cellphone network is probably off topic for most of the newsgroups listed above. Therefore, I suggest you redirect your queries/confusions to more appropriate groups.   Bruce .   --

"Kerr Mudd-John" <admin@127.0.0.1>: Sep 15 11:53AM +0100 On Wed, 14 Sep 2016 08:54:56 +0100, Frank Slootweg   > You don't ask a dumbed down question, but a dumb question and your > 'question' isn't a question, but a false statement.   > HTH.   It's a xposting troll.   -- Bah, and indeed, Humbug

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